1. Field of the Invention
The present invention relates to photography and more particularly to folding cameras.
2. Description of the Prior Art
In recent years, self-processing cameras have become very popular among amateur photographers. For reasons well known to those skilled in the photographic art, such cameras necessarily require large format film and dictate the use of relatively long focal length objective lenses in order to provide reasonably large finished prints. Accordingly, self-processing cameras are often of the folding type which was common among conventional cameras at the time when the formats of most amateur camera films were correspondingly large. The lens and shutter assembly of a typical known folding camera is carried by a lens-supporting board or member that is connected to the camera housing by a collapsible bellows and supported by a parallelogram linkage that maintains the lens in parallel relation to the housing. Alternatively, it is also known to support the lens at one end of a board that is hinged to the housing at its opposite end and provided with a collapsible bellows that allows the board to move between an open position in oblique relation to the housing and a closed position in which a surface of the board is located either fully flush with or approximately flush with the camera housing. Cameras of this latter type are described, for example, in U.S. Pat. Nos. 785,239; 2,880,658; 3,665,831; 3,677,160 and 3,693,526. The latter patent describes a folding camera that includes, in addition to the lens-supporting board, a door for covering the lens when the camera is in its folded state. In addition to protecting the lens, the lens-covering door also includes a latch for preventing the board from inadvertently moving out of its folded position. The camera may be erected by movement of the lens-covering door to an inoperative position wherein it remains while the board is moved to its erected position.
One problem requiring consideration in the design of folding cameras is that of alignment of the objective lens so that it is correctly positioned relative to the film plane when the camera is erected. To ensure this alignment, the camera must remain substantially rigid when erected so that forces applied by the user during an exposure will not alter the optical geometry of the camera. In addition to being rigid, the camera's erecting mechanisms must also position the lens at an appropriate distance from the film plane each time the camera is erected. To these ends the prior art, as exemplified by the aforesaid patents, suggests that a jointed strut be provided between the housing and the lens supporting board. In order to erect and fold these cameras the operator is obliged to grasp portions of the camera adjacent the lens or the bellows thereby creating an opportunity for either fingerprints being lodged on the lens or distortions being imparted to the bellows. Distortion to the bellows may be such as to move a portion of the bellows into the optical path between the lens and the film thereby blocking a portion of the periphery scene from being photographed. To preclude this, the bellows may be provided with rigid sections as suggested in the prior art but this entails additional expense.